A geofence is a virtual fence surrounding a geographic location and provides notification when a mobile device enters or leaves the geofence. Geofence capability is getting increased attention in the smartphone application and gaming market. Many application developers are creating innovative use-cases for geofences. Such examples include child location services which can notify the parents when a child leaves a designated area, wildlife management which sends alerts when wildlife strays into farmland, or advertising services which can send out coupons or offers when a person is near a shop.
A variety of positioning technologies, such as standalone GPS/GNSS (Global Positioning System/Global Navigation Satellite System), AGPS/AGNSS (Assisted GPS/GNSS), WWAN (Wireless Wide Area Network) signal based, Cell-ID based, Wi-Fi based, Sensors based, may be used to track the location of a geofencing mobile device. Continuous tracking of a mobile device results in very responsive geofence performance with high power consumption that reduces battery life. Providing responsive geofence solutions in a power optimized way can be a challenge.